Field of the Invention
The present invention is generally related to urinary catheters as used for draining the bladder of patients suffering from urinary retention or by disabled individuals who have no way of controlling urination, and is particularly concerned with a urinary catheter which allows voiding of the bladder with reduced risk of urinary tract infection.
Related Art
Persons with urinary retention due to spinal cord injury, multiple sclerosis, prostate enlargement, or the like use disposable urinary catheters, referred to as intermittent catheters, to void their bladder. The process of catheterization can be messy and sometimes leads to urinary tract infections.
The state of the art is to slide a flexible plastic tube up the urethra and into the bladder. The tube is often heavily lubricated in an effort to reduce damage to the urethra due to surface abrasion caused by the sliding of the catheter against the urethral walls. The state of the art has changed relatively little in general method with most recent developments occurring in the area of coatings, lubrication, and packaging, for example as described in WO 1998011932, EP0909249, WO 2013075725, US 2012/0325692, WO 2002011810, EP 1786591, EP 2226042, WO 2001062315, and EP 1131022. All of these catheters rely on the catheter (usually with lubricant coating) being forcefully slid through the urethra with sliding of the catheter tube against the wall of the urethra. Micro trauma from this sliding can be a source of urinary tract infection. The exterior surface of the catheter can become contaminated with bacteria when sliding through the male urethral meatus which then are carried up into sterile regions of the urethra and into the bladder, potentially causing urinary tract infection. The risk of infection is reduced by use of an insertion tip which opens up the entry of the urethra, with the catheter sliding through the insertion tip into the urethra. However, bacteria are still present at the end of the insertion tip and can be picked up and carried by the leading end of the catheter into the bladder.